The model reviewed is this one:
https://redidriver.com/my-redi-driver-store/redi-driver-boss-with-3-18-barrel-2-sleeve-free-shipping/

It was rented from www.townequipment.ca in Ottawa. Super good service, $65/day and free delivery.

So the sucker weights 35lbs. Probably a bit more with fuel. It is totally manageable by one guy in reasonable shape. Trying to get it on top of 8' t-posts when I forgot to bring my ladder was a bit of a challenge though and by my eighth post my arms were dying. Good thing I only had 10 posts at that site to do. The t-posts and 2 7/8" posts done at home from a ladder were a piece of cake in comparison.

It's a 4 stroke engine so uses regular gas. I used V-power from Shell as no Ethanol to eat everything up. They say 1 gallon is good for 1000 t-posts. I got about 45-60 min of non-stop use on one tank of gas. I was the first renter and rapidly ran into an issue. The engine would stall after 3-5 seconds. I called redidriver.com and they told me it was a defect and Honda had a fix. They e-mailed it to me. The fuel return line is too long so it crimps a bit and forms a kink which causes blockage and floods the engine. The solution is to remove 4mm but in the end I needed to remove the sleeve and a total of 8mm to resolve the issue. From then on it worked perfectly and I was able to run it non stop with no issues.

T-posts would drive 3 feet into my heavy clay in 5-10 seconds. The real test was driving 2 7/8" schedule 40 galvanized posts 3 feet 6" at a 60 degree angle into my heavy clay to serve as end posts for my grape trellis. Yes it is only 50 foot rows and I am running Geneva double curtains for table grapes so these posts are way over-engineered but I plan on being carried out of this house feet first and when I am these posts will still be standing strong. Really posts that size were borderline for this tool but it DID get the job done. I only had 4 posts but if I had more than that to do in the future or if I had rocky soil where it could get caught up I would have rented a heavy duty ground based post driver. It took between 12-15 min of SOLID non-stop driving to get them in the 42 inches (honestly it was more like 38-39" when I generally gave up and said good enough).

So would I recommend this tool? In a heartbeat. Hand held you could quickly move from one post to the next. If you pre-planted your posts prior to renting you could do this as a one man job. Or if you had 2 guys one could go ahead and pre-stick and the follow up guy comes to drive it. This could quickly be one with the guy carrying the drive in one hand and a 2-3 foot stool for height in the other hand. Would work good for fence posts too.

I probably would have hand hammered in my T-posts but there was no way I could manually drive the 2 7/8" ones. Local quotes were $350 minimum setup fee and $30 per post for someone to come and do it so $65 + tax + gas was a steal.

You can see the before/after below. The black electrical tape marker is at 42". I laid an undriven post on top of the driven post so you can better see the job done. The t-posts there were my guide for 60 degree angle for the post and then 60 degree angle for my gripple earth anchor.